I'm a ways down the road from you, but there is a place in Lancaster that fills them cheap. I pay $7 or $8 for 5lbs. They don't swap either, just fill. It's a fire equipment place that sells and refills fire extinguishers. It's called Trost Fire equipment, on Walden. I can't help you much for Rochester, but check with fire equipment places if you don't want to shuffle off to Buffalo..

I've had mine filled at Monroe Extinguisher on Dodge St. I also bought both of my CO2 tanks there. I bought two 15lb tanks which were filled, for $50 each. This was a few years ago, so the price may not be the same. Another nice thing is that if your tank is expired, they will take the old one and replace it with another (or test it, i don't remember which). They are used tanks but perfectly usable and tested.

I've had mine filled at Monroe Extinguisher on Dodge St. I also bought both of my CO2 tanks there. I bought two 15lb tanks which were filled, for $50 each. This was a few years ago, so the price may not be the same. Another nice thing is that if your tank is expired, they will take the old one and replace it with another (or test it, i don't remember which). They are used tanks but perfectly usable and tested.

Good call on Monroe Extinguisher! I picked up a used full 5# tank there on Saturday for $45!